Water: Taking the Phosphates Out of Detergent Leaves a Cleaner Planet—But Are the Dishes Dirtier?

The Spokane river had a soap scum problem. Over the years the runoff of nutrients like phosphorous into the eastern Washington state waterway has encouraged the growth of algae, leading to green, icky waters in a process science teachers would call eutrophication and swimmers would call icky. As the algae proliferates and then dies, their decomposition eventually sucks oxygen from the water, which is not good for aquatic life. (A similar process creates “dead zones” in coastal waters, including the Gulf of Mexico.) While there are many potential sources of nutrient runoff—including fertilizers and human waste—a group of environmentalists led by the Sierra Club focused on dishwasher detergents, which at the time contained up to 8% phosphate content by weight. With the assistance of some friendly Washington state legislators—and against the efforts of the cleaning industry—greens pushed through a ban on phosphates in detergents in 2006, helping to significantly reduce the phosphorus reaching Spokane water treatment plants. (Though signed in 2006, the ban was only rolled out for the entire state this year.) “There was a really broad constituency for the idea of getting these chemicals out of the system,” says Rachael Osborn, a public interest water lawyer who worked with Sierra Club on the campaign.

Apparently—16 states now ban phosphates in automatic dishwasher detergents, and on July 1 the industry trade group representing most detergent manufacturers accepted a voluntary ban. (The bans allow up to 0.5% phosphate content, but that’s because completely eliminating the chemicals from a detergent formula is virtually impossible.) That means it won’t be long before dishwater detergents with phosphates will be essentially gone from U.S. store shelves—which represents a major victory for clean water advocates. “Phosphorus is a known pollutant,” says Jonathan Scott, spokesman for Clean Water Action. “If we remove it upstream [in detergents] we won’t have to spend to remove it downstream.”

But it turns out there may be a catch. There’s a reason detergent makers have used large amounts of phosphorous—it works. Phosphates don’t directly clean—rather, the chemicals bind with dirt and keep it suspended in the wash water, allowing the cleaning agents to do their work. (Since the NBA season just began—go 76ers, I guess—here’s a basketball analogy: phosphorus is the point guard, dishing out the assists.) Phosphorus is especially useful in regions with hard water, where minerals in the water can otherwise interfere with cleaning agents. “Phosphorous is just amazing in grabbing onto stuff,” says Dennis Griesing of the lobbying group American Cleaning Institute, in an almost wistful fashion. “It’s a very sociable element.”

Consumer Reportsrecently tested 24 top phosphate-free detergents and found several that scored “very good” on the magazine’s scale—with Finish Quantum leading the pack. But none of the greener detergents left the cutlery as clean as did the top (phosphate-filled) products from past trials—and they often cost more. Some consumers are even rebelling. When Washington first instituted its ban, some residents reportedly drove across state lines to Idaho to smuggle in phosphate-full detergents. And customers have left angry comments about dirty dishes on detergent manufacturer’s websites.

Green advocates say that phosphate-free detergents can clean just fine, and will get better over time. In place of phosphates, manufacturers have found substitutes, including enzymes, sodium citrate and sodium carbonate. “This is a wonderful example of how regulations can spur innovation,” says Martin Wolf, director of product sustainability and authenticity for Seventh Generation, which has made phosphate-free detergents for years (and which, perhaps not surprisingly, helped push for the phosphate ban.) Perhaps—the story of environmental regulations is the story of industry fighting, then adjusting, then thriving. But especially in the short-term, there can be a cost to switching to some greener products—a private cost (dirtier dishes), balanced by a public benefit (cleaner water). That’s a decent trade-off to me—as anyone who’s been to my apartment knows, my glassware is less than Martha Stewart—but it is a trade-off.